4-(2,2-Dimethyl-1-oxopropyl)-benzamide → 4-(2,2-dimethyl-1-oxopropyl)-N-[4-(2,2-dimethyl-1-oxopropyl)-benzoyl]benzamide

Participants

Reaction Conditions

Reaction Steps

A solution of 12.3 grams (60 mmol) of 4-(2,2-dimethyl-1-oxo-propyl)-benzamide dissolved in 450 ml of THF is chilled to 5° C.; and 20.6 grams of 35% potassium hydride in oil washed twice with hexane is added as a suspension in hexane. The resulting mixture is stirred for hours at 5° C. A solution of 13.8 grams (61.4 mmol) of p-pivaloyl-benzoyl chloride dissolved in 100 ml of THF is added with stirring over a period of 21/2 hours at 5° C. Sitrring is continued for an additional hour at this temperature, following which the mixture is stirred into 500 ml of an ice-cold saturated NH4Cl solution. The liquid phases are separated, and the aqueous phase is extracted with t-butyl methyl ether. The combined organic layers are washed with saturated sodium chloride solution, separated, and dried over magnesium sulfate. After filtering off the magnesium sulfate, the filtrate is evaporated to a solid, and the crude product is partially purified by chromatography on silica with CHCl3 eluant. The resulting product is twice crystallized from isopropyl alcohol and then from methylene chloride/t-butyl methyl ether, yielding the title product (mp 132°-134° C.).

Provenance & Evidence